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Topic summary · Decision maths (D2)

Dynamic Programming summary

Dynamic programming builds an optimum from overlapping subproblems using stage–state tables.

Files: D2-Dynamic Programming.pdf · D2-Dynamic Programming answers.pdf · free public downloads · diagrams in the PDFs

Key learning points

  • Define stages and states before filling numerical values.
  • Reuse optimal sub-route costs (Bellman principle).
  • Work systematically — often backwards from the end.
  • Recover the policy by tracing the argmin/argmax decisions.

Worked example 1 — Memoisation

Why store the best cost to each state?

Working

reuse it later without recomputing\text{reuse it later without recomputing}

That reuse is the core DP idea.

Worked example 2 — Define stages and states before filling numerical value

Use this method from the Dynamic Programming sheet: Define stages and states before filling numerical values.

Working

Attempt a matching question on the sheet, then check the Answers PDF.\text{Attempt a matching question on the sheet, then check the Answers PDF.}

Each key learning point matches a question type on the printable worksheet.

Worked example 3 — Reuse optimal sub-route costs (Bellman principle)

Use this method from the Dynamic Programming sheet: Reuse optimal sub-route costs (Bellman principle).

Working

Attempt a matching question on the sheet, then check the Answers PDF.\text{Attempt a matching question on the sheet, then check the Answers PDF.}

Each key learning point matches a question type on the printable worksheet.

Worked example 4 — Work systematically — often backwards from the end

Use this method from the Dynamic Programming sheet: Work systematically — often backwards from the end.

Working

Attempt a matching question on the sheet, then check the Answers PDF.\text{Attempt a matching question on the sheet, then check the Answers PDF.}

Each key learning point matches a question type on the printable worksheet.

Worked example 5 — Recover the policy by tracing the argmin/argmax decisio

Use this method from the Dynamic Programming sheet: Recover the policy by tracing the argmin/argmax decisions.

Working

Attempt a matching question on the sheet, then check the Answers PDF.\text{Attempt a matching question on the sheet, then check the Answers PDF.}

Each key learning point matches a question type on the printable worksheet.

Scaffolded Learning Sheet and answers (PDFs)

This page is a short, searchable overview for revision and search engines. Use the Scaffolded Learning Sheet first, then the Answers PDF for a full written solution. The printable PDFs remain the main classroom resource.